repal postive to postive or negitve to negtive
A because the ball is moving up (kinetic) and the higher it goes the greater the potential energy when it'll fall.
Answer:
(a). The power delivered to the element is 187.68 mW
(b). The energy delivered to the element is 57.52 mJ.
Explanation:
Given that,
Charge 
Voltage 
Time t = 0.3 sec
We need to calculate the current
Using formula of current

Put the value of charge



(a).We need to calculate the power delivered to the element
Using formula of power

Put the value into the formula



Put the value of t



(b). We need to calculate the energy delivered to the element between 0 and 0.6 s
Using formula of energy

Put the value into the formula





Hence, (a). The power delivered to the element is 187.68 mW
(b). The energy delivered to the element is 57.52 mJ.
Permanent magnets are important for their industrial uses especially when it comes to power generation and electric motors. The induction process for turbines and generators needs permanent magnets to turn mechanical motion into energy.
Exposing magnetized magnets to opposing external fields produces a demagnetizing effect. This effect is most apparent in permanent magnet materials having a non-linear demagnetization curve, such as Alnico. ... Other factors such as SHOCK and VIBRATION have very little effect on today's permanent magnet materials.